Torch



Nov. 25, 1930. P. M. FORSTER TORCH Filed Nov. 26, 1929 TOR. W

1* A TTORNEYS.

gamed Nov. 25, 1930 UNITED STATES PERCY M. FORSTER, F BERKELEY,CALIFORNIA TGRCH Application filed November 26, 1929. Serial No.409,837.

This invention relates to blow torches and has for its principal objectthe provision of a simple and efiicient blow torch capable of utilizingnatural gas as a fuel.

In carrying the invention into practice the air andmatural gas areadmitted to a primary chamber in the torch and caused to mix beforebeing ejected at the burner tip. This holds the flame closely adjacentto the tip which is, of course, essential. To create a flame of intenseheat for welding or burning, the torch is constructed so that oxygen orcompressed air or both may be ejected directly at the burner tip.

Gne form which the invention may assume is exemplified in the followingdescription and illustrated by Way of example in the accompanyingdrawings, in which:

Fig. 1 is a side elevation of a torch embody ing the preferred form ofmy invention.

' r Fig. 2 is a central section through the same.

Fig. 3 is a transverse sectional View taken on line III-III of Fig. 2.

Referring more particularly to the accompanying drawings, 10 indicatesa. torch or burner utilizing natural gas as a fuel. This torch or burnercomprises an exterior or outer casing 11 preferably cylindrical in formand having one end restricted as at 12. Arranged within this outercasing 11 is an inner tube 1% which is joined with the outer casing 11at the restricted end 12 thereof. As the tube 1 1 is considerably lessin diameter than the casing 11 a primary mixing chamber 15 is formedthe'rebetween. The tube 1% terminates short of the end of the casing 11opposite the restricted end 12 thereof. At this point a perforatedbaffie plate 16 is interposed etween the tube 14 and the casing 11 andis, of course, disposed Within the primary mixing chamber 15.

The end of the casing 11 which is opposite its restricted end 12 is whatI prefer to term the inlet end of the torch. Projecting through this endof the casing is a gas and air pipe 17 which projects into the primarymixing chamber 15 to a point just short of the restricted end 12 of thecasing 11. At its outer end this pipe 17 is fitted with a T 18 so thatit may be connected to a source of natural gas by a pipe 19 and a sourceof compressed air by a pipe 20. Both of these pipes are fitted withcontrol valves 21 which may be manipulated to regulate the amount of airand gas injected into the casing 11 through the pipe 17.

' The end of the tube'ld at the restricted end of the casing 11 is openso as to form a burner opening or nozzle 22. Arranged concentricallyWithin the tube 14 is a compressed air and oxygen pipe 23. This pipeextends longitudinally through the burner and its outer end projectsslightly beyond the burner nozzle 22-as illustrated in the drawings. Theother end of the pipe 23 is fitted with a T 24L which connects with anoxygen inlet pipe 25 and a compressed air inlet pipe 26. These pipes areboth controlled by regulating valves 27 so that the amount of oxygen orcompressed air admitted to the pipe 23 for ejection at the burneropening may be controlled.

, In operation of the device the pipe 19 is connected with a source ofnatural gas, as it is the object of the present invention to provide aburner utilizing natural gas as a fuel. The pipes 20 and 26 areconnected with a source of compressed air and the pipe 25 is. connectedwith a source of oxygen. To start the burner the valves 21 of the pipes19 and 20 are opened a proper amount and the natural gas and compressedair is discharged into the primary mixing chamber 15 adjacent therestricted end of the casing 11.

In order, to discharge at the burner nozzle 22 the gas and air injectedinto the casing 11 from the pipe 17 must travel along the primary mixingchamber 15 through the perforated baflie plate 16 and then along theentire length of the inner tube 14:. The air and gas are caused to swirlin the primary mixing chamber 15. This, together with the passing of thegas and air through the bafile 16, thoroughly mixes the gas and air sothat a combustible mixture will be discharged at the urner nozzle 22which may be ignited. This is very important as it enables the flame tobe maintained close to the burner opening or nozzle, which is essential.

I desire to point out that the lack of air in I natural gas prevents itfrom igniting until it has mixed with a suflicient quantity of air.Thus, if the natural gas and air were ejected directly at the nozzlewithout first mixing the same the flame would be spaced from the nozzleand result in an inoperative burner. I overcome this, of course, byfirst mixing the air and gas before discharging it under pressure fromthe nozzle.

If it is desired to obtain a flame of intense heat for welding orcutting, compressed air or oxygen can be discharged from the pipe23 at apoint just beyond the nozzle 22. As the tip of the pipe 23 extends justbe ond the burner nozzle the gas flame will not blown away from thenozzle. This is likewise important.

I have found in actual practice that a burner constructed in accordancewith my invention is very efiicien't for use in connection with naturalgas and can be regulated so as to obtain a flame of desired heat.

While I have shown thepreferred form of my invention, it is to beunderstood that va-- rious changes may be made in, its construction'bythose skilled in the art without departing from the spirit of theinvention as defined in the appended claims.

Having thus described my invention, what I claim and-desire to secure byLetters Patent where the gas and air must reverse its irec tion of flowbefore passing through the tube to the nozzle.

3. A torch including a casing, a tube arranged therein and terminatingat one end in agnozzle, a mixing chamber surrounding the tube andcommunicating therewith at the other end thereof, means for deliveringgas and air to the mixing chamber at a oint where the gas and air mustreverse its 'rection of flow before passing through the tube to thenozzle, a perforated baflie plate interposed between the tube and mixingchamber to assist in mixing the gasand air.

4. A torch including a casing, a tube therein' terminating in a nozzle,means for delivering gas and air into the casingwhereby it will passthrough the tube and discharge at nozzle, said pipe projecting a slightdistance beyond said nozzle.

5. A torch including a casing, a tube arranged therein and terminatingat one end in a nozzle, a mixing chamber surrounding the tube andcommunicating therewith at the other end thereof, means for deliveringgas and air to the mixing chamber whereby it will pass from the mixingchamber through the tube and discharge at the nozzle, and a. pipearranged to extend through said tube for delivering oxygen andcompressed air' at the nozzle.

6. A torch including a casing, a tube arranged therein and terminatingat one end in a nozzle, a mixing chamber surrounding the tube andcommunicating therewith at the other end thereof, means for deliveringgas and air to the mixing chamber at a point where the gas and air mustreverse its direction of flow before passing through the tube to thenozzle, and a pipe arranged to extend through said tube for deliveringoxygen and compressed air at the nozzle.

7. A torch including a casing, a tube arranged therein and terminatingat one end in a nozzle, a mixing chamber surrounding the tube andcommunicatin therewith at the other end thereof, means far deliverin gasand air tothe' mixing chamber where y it will pass from the mixingchamber through the tube and discharge at the nozzle, 9. perforatedbaffle plate interposed between the tube and mixing chamber to assist inmixing the gas and air, and a pipe arranged to extend. through said tubefor delivering oxygen and compressed air at the nozzle.

PERCY M; FORSTER.

the nozzle, a pipe arranged concentrically of the tube for deliveringoxygen and air at the g

